1. Field of the Invention
The invention relates to a method and an apparatus for lubricating the bearings of a turbocharger with a portion of the lubricating oil of an internal combustion engine attached to the turbocharger.
2. Discussion of Background
It is known to supply the lubricating-oil circuit of a turbocharger with the lubricating oil of an internal combustion engine. The relatively large lubricating-oil flow of an internal combustion engine is only coarsely filtered, for instance with a mesh width of 50 .mu.m. This is certainly adequate for most lubricating points, but not for the bearing arrangement of a turbocharger of high efficiency. The latter, on account of the relatively high rotary speeds and the narrow lubricating gaps, requires lubricating oil of finer consistency, which cannot be provided by the hitherto known lubricating-oil systems of internal combustion engines.
If the intention were to filter all the lubricating oil to the order of magnitude of about 5 to 10 .mu.m required by the turbocharger, a plurality of fine filters would have to be installed. The filter cartridges would then become clogged very quickly on account of the resulting extreme increase in the cleaning volume, so that the lubrication of the turbocharger would be put at risk without the expensive exchange of the filter cartridges.